Feed table and height control for duplicating machines



H. R. GULLIXSON ET AL 2,831,682

April 22, 1958 FEED TABLE AND HEIGHT CONTROL FOR DUPLICATING MACHINES Original Filed Nov. 27. 1946 5 Sheets-Sheet l April 22, 1958 H. R. GULLIXSON ETAL 2,831,682

. FEED TABLE AND HEIGHT CONTROL FOR DUPLICATING MACHINES Original Filed NOV. 27. 1946 5 Sheets-Sheet 2 .4%M MW April 22, 1958 H. R. GULLIXSON ETAL 2,831,682

FEED TABLE AND HEIGHT CONTROL FOR DUPLICATING MACHINES 5 Sheets-Sheet 3 Original Filed Nov. 27. 1946 April 1958 H. R. GULLIXSON ETAL 2 FEED TABLE AND HEIGHT CONTROL FOR DUPLICATING MACHINES Original Filed Nov. 27. 1946 5 Sheets-Sheet 4 April 22, 1958 H. R. GULLIXSON ETAL 2,831,682

FEED TABLE AND HEIGHT CONTROL FOR DUPLICATING MACHINES Original Filed Nov. 27. 1946 5 Sheets-Sheet 5 anvil/WW5 FEED TABLE AND HEIGHT CONTROL FOR DUPLICATIN G MACHINES Harold R. Gullixson, Greensboro, N. C., and Herbert F. Bruns; Chicago, 11]., assignors to Ditto, Incorporated, Chicago, Ill., a corporation of West Virginia Original application November 27, 1946, Serial No.

712,538, now Patent No. 2,660,113, dated November 24, 1953. Divided and this application November 20, 1953, Serial No. 393,384

4 Claims. (Cl. 271-62) This invention relates to duplicating machines of the offset type and more particularly to a feed table and height control mechanism therefor which is suitable for use in such machines.

This application is a division of applicants co-pending application Serial No. 712,538, filed November 27, 1946, entitled Rotary Offset Duplicator, now Patent No. 2,660,113, issued November 24, 1953.

It is an object of this invention to provide a pneumatically operated feed table which is adapted to maintain a stack of sheets to be fed into the duplicating machine at the proper height for feeding throughout the printing process.

Another object is to provide a control mechanism which automatically maintains the stack of sheets at a particular height during the feeding process.

Still another object of this invention is to provide a mechanism of the character described which requires a minimum amount of attention from the operator and which does not readily get out of adjustment.

Yet another object of this invention is to provide a control mechanism for a feed table of the character described which will permit the raising and lowering of said table by operation of manual controls which are conveniently accessible to the operator at the front of the machine.

Another object of this invention is to provide a sheet- 2 table and height control mechanism therefor which is of relatively simple construction and therefore which may be manufactured at a minimum of expense.

Further objects and advantages of this invention will become evident as the description proceeds and from an examination of the accompanying drawings which illustrate one embodiment of the invention and in which similar numerals refer to similar parts throughout the several views.

In the drawings:

Figure l is a view in vertical cross section through a duplicating machine which has been provided with a feed table and height control mechanism embodying the invention.

Figure 2 is a view in side elevation of the machine shown in Figure l, the view being taken from the opposite direction with certain parts removed.

Figure 3 is an enlarged view in elevation of the portion of the machine shown in Figure 1 which incorporates the feed table and the parts immediately associated therewith.

Figure 4.is a section taken substantially along the line 4-4 of Figure 3.

2,831,682 Patented Apr. 22, 1958 Figure 8 is a section taken substantially along the line 8-8 of Figure 6.

Figure 9 is an enlarged elevational view of a portion of Figure 6.

Figure 10 is a somewhat diagrammatic representation of the pneumatic system controlling the position of the feed table.

As shown in Figures 1 and 2 the illustrative machine which incorporates the feed table and height control mechanism to be described herein is designed for support on a desk or table. The machine comprises a main frame which includes two parallel side plates one of these plates 80 being shown in Figures 1 and 2.

Supported between the plates is a main cylinder 82- which, in the operation of the machine, rotates counterclockwise, Figure 1, and below and rearwardly of the cylinder is a motor 83 which drives all of the driven devices, these including a combined vacuum and pressure pump 84. The motor-pump unit is mounted on a plate 85 whose ends are secured to the side walls, so that the plate also constitutes a cross member of the frame.

Reference numeral 86 designates stack supporting means mounted on a pair of tie rods 77 and78 which extend between the side walls, the stack supporting means including automatic elevating and height adjusting mechanism. Reference numeral 87 designates automatic sheet feeding and detector means, while reference numeral 88.

designates feed rollers and paper stop means located beneath the forward half of the cylinder 82. Reference numeral 96 designates a desensitizing device located beneath the main cylinder somewhat rearwardly of the central vertical plane of the latter. A blanket roll 89 is mounted behind the cylinder and behind the roll is roll cleaning mechanism 90. Moistening mechanism is gen erally indicated at 91 and inking mechanism at 92, the two being in superposed relation at the front of the cylinder. Reference numeral 93 designates cleaning means for an inking form roller. mechanism is indicated at 94, reference numeral 95 designating a paper receiving tray.

Referring now to Figure 3 as shown therein, a plate' ers 220 and 221 in a vertical slot 222 formed in the side Figure 5 is a section taken substantially along the line 5-5 of Figure 3.

, Figure 7 is a section taken substantially along the line 7----7 of Figure 6.

plate 80, and, as shown in Figure 7, the stem of bolt 217 is continued beyond the side plate and supports a horizontal axle 223 upon which are mounted rollers 224 and 225 adapted to roll on the outer margins of slot 222.

Plate 215 similarly supports a pair of vertically spaced rollers, of which the top one appears at 226, Figure -6, working in a vertical slot 227 directly opposite slot 222, the lower bolt being extended past side wall 81 and supporting rollers 228 and 229 which roll on the outer margins of slot 227. The vertically spaced rollers working in slots222 and 227 guide the table 213 for strictly vertical movement, the closed top and bottom ends of the slots serving as stops for the rollers whereby to positively limit the up and down travel of the table. Rollers 224, 225, and 228, 229, prevent lateral displacement of, the table.

Pivoted on rod 78 is a U-shaped bar 230 including arms 231 and 232 which project beneath the table and have out-turned ends mounting co-axial rollers 233 and 234 which are guided in opposed channels 235 and 236 Paper stripping and delivery s fixed in parallel relationbeneath. the table. thus stabilized against. any lateral wobble.

The table is The top of the table is provided with a central fore and aft T slot 237 and with intersecting transverse T slots 238and 239." Slidable in slot 237 is the tongue 240 of a back stop 241 in the form of a triangle which extends the width of the table and whose sides 2 2 and 243 are each inclined seven degrees from the altitudeof the triangle, the altitude being perpendicular to tongue-$2.40. Thus, while the stack S, Figure 3, is supported on the table at a seven degree inclination to the horizontal, the

rear end of the stack is in a vertical plane against the back stop. Should the required adjustment of the back stop he snchthat the tongue 2443 might interfere with:

246 in the required position, or can be loosened to permit adjustment of the rod along the top of the stack fore and aft. Slidable upon the rod 246 is the head 251 of a T fitting 252, the fitting being lockable in any required position on the rod by means of a thumb screw 253. The fitting includes a depending hollow shank portion 254 which is closed at its upper end and therebeneath is provided with a communicating nipple 255. Threaded on the lower end of the shank 254 is a tubular member 256 adapted to be-locked in adjusted position by means of a knurled nut 257. The lower portion of member 256 is inwardly thickened to provide a cylindrical passage 258 which is vertically grooved to provide open-ended channels 259. Fixed to the outer extremity of member 256 is a disc 261 having a tapered opening providing a seat for a ball 262 whosediameter is very slightly less than that of the cylinder 258. The ball is normally supported on the seat slightly below its maximum diameter. Its movement away from the seat is limited by a pin 263 which extends across the cylinder 258 and is so disposed that when abutted by the ball, the ball will still project substantially outwardly of the seat, as shown in Figure 4.

Referring to Figures 2 and. 10, a pipe or tube 264 is connected to the. pressure sideof pump 84 through a control and relief valve 265. Branched from pipe 264 is a pipe 266 which. extends forwardly outside of wall.

80 and upwardly to have its. upper end connected through a flexible hose 266'. with nipple255 of the fitting 2'52.v

Interposed in pipe 266 are a control and shut off valve 267, a check valve 268, and an orifice plate or choke 269, in that order. Beyond the choke, a pipe 270 connects pipe 266 with bellows 211. A by-pass 271 is arranged around valve 268 andchoke 269 and includes a normally closed control valve 272 and a normally closed relief valve 273; Hose 266 isled through van opening 274 in side wall 30 and is long enough to permit fitting 252 to be mounted at the extreme right of bar 246. When the fitting is otherwise positioned, the slack can be pushed or pulled back through theside wall opening.

Assuming the table 213 to be in a lowered position with the stack out of contact with ball 262, the latter will be seated so as to prevent air escape past it. The entire pressure is, therefore, delivered through the check valve and choke to the bellows and the latter expands, lifting the stack into engagement with the ball. The .unseating of'the ball, whose escape area is greater than that of the choke, permits escape of pressure past it through channels 259 with the result that the stack is sustained in a definite balanced position. That is to say, the pressure which would seek to expand thebellows further is exhausted past the ball and a definite balance is maintained. As asheet is removed from the top of the stack the stack is immediately lifted by that much and the balance again established.

Should the pump be stopped, the check valve 263 will prevent the stack from. dropping beyond the point at which the ball again seats. Should it be desired to elevate the stack rapidly, valve 272 can be opened, thus by-pasing the choke 269, and if it should be desired to lower the stack rapidly the relief valve 273 can be opened.

Due to the provision of the adjustable stack-confining means, such as 241, 244 and 245', stacks of variously sized blanks can be positioned variedly on the table 213. Due to the fore and aft adjustability of the bar. 246 and thelateral adjustability of the fitting 252, thejlatter can be readily positioned in the necessary relation to the stack as permitted by the, flexible hose. In Figures 3 and 10 the fitting 252 is adjacent the rear end of the stack and this is an ordinarily desirable relation- =ship since the pressure escaping past the ball helps to hold down the rear end of the top blank. Since the ball is prevented by pin 263 from being pushed completely within member 254, the stack can never be jammed against the seat washer 261 so as to block escape through the latter.

A sheet of plate metal, Figure 1, is bent on a radius to provide angularly related portions 276 and 2'77 which are supported by bars 278 and 279 whose ends are fixed to the side walls. Portion 276 is vertically disposed and extends along the inner end of table 213 and downwardly through the range of travel of the table with its front surface just clear of the table edge. Portion 277 projects rearwardly of the machine in parallel relation to table 213 and has a fiat top surface substantially in continuation of the top sheet of the stack on the table for the reception and support of the fed sheets. Should it be desired to feed by hand, the valve 267 is closed so that pressure is cut oil from the stack'lifting and control devices. Hose 266' may be disconnected from fitting 252, and the latter together with bar 246 may be removed by suitably threading nut 254) away from wall 80. For hand feeding, the top of the table should be substantially flush with the top of guide plate 277. Upon manually lifting the table, it can be locked in this position by hooks as at 280, Figure 3, pivoted to the side walls above slots 222 and 227 and engageable under the spacers for rollers 220 and 226. The latches as at 25% are normally retained in the position shown in Figure 3, clear of the slots, by any suitable friction or detent means.

With the machine at rest, the operator, for automatic sheet feeding, places a stack on table 213, the latter being in its lowered position. This table is at an inclination, here shown as whereas end guides 2,41 and 276 are vertical, as previously described. Consequently, when the operator places the stuck on the table against the head guide and moves the tail guide against it, the sheets are all slightly displaced relative to each other so as to be loosened, and a bevel is applied to the ends of the stacks, that at the head end greatly facilitating the actionof the air separator, Thisinclination diminishes the tendency of the top sheets to crawl ahead in automatic feeding and also gives somewhat more operat ing room at the front of the machine. it may be mentioned that in hand feeding, the inclination limits the tendency of the manually held stack to crawl ahead.

With the table loaded, main switch 723 is closed so that themotor starts and the pump 84 is operated. Pressure is thus supplied to the bellows 211 as previously described so that the bellows lifts the stack up to the proper feeding height as controlled by the ball valve 252.. Various other adjustments are then carried out as fully described in the above mentioned co-pending application and subsequently the feeding of sheets is begun with the feed table being maintained at the proper height for proper feeding.

" ln the drawings and specification, there have been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation. Changes in form and in the proportion of parts, as well as the substitution of equivalents are contemplated, as circumstances may suggest or render expedient, without departing from the spirit or scope of this invention as further defined in the following claims.

It is claimed:

1. Elevating and height control apparatus for a stack of blanks comprising a vertically movable table, expansible chamber means in operative association with said table, air supply means for supplying air under pressure to said chamber means for elevation of said table, and means for venting a portion of the air from said air supply means to atmosphere when said table is raised to a certain height whereby to reduce the pressure supplied to said expansible chamber means.

2. Elevating and height control apparatus for a stack of blanks comprising a vertically movable table, expansible chamber means in operative association with said table for elevation thereof, means for supplying air under pressure to said expansible chamber means, and means for reducing the air pressure to said expansible chamber means when said table is raised to a certain height, said latter means including a relief valve connected to said air supply means for venting a portion of the air to atmosphere.

3. Elevating and height control apparatus for a stack of blanks comprising a vertically movable table, expansible chamber means in operative association with said table, means for supplying air under pressure to said expansible chamber means for elevation of said table, and means for reducing the air pressure to said expansible chamber means as said table is raised to a certain height including a choke and a relief valve, said choke having an orifice of reduced diameter located in said air supply means, said relief valve connected between said expansibie chamber means and said choke.

4. Elevating and height control apparatus for a stack of blanks comprising a vertically movable table, bellows means for supporting and elevating said table, air supply means for supplying air under pressure to said bellows means, and means connected to said air supply means for venting a portion of the air from said air supply means to atmosphere when said table is raised to a predetermined height.

References Cited in the file of this patent UNITED STATES PATENTS 1,061,526 Cortissoz May 13, 1913 2,247,466 Baker July 1, 1941 2,530,670 Von Hofe Nov. 21, 1950 

